difftreelog
feat automatic rollback
in: trunk
10 files changed
Cargo.lockdiffbeforeafterboth--- a/Cargo.lock
+++ b/Cargo.lock
@@ -610,6 +610,12 @@
]
[[package]]
+name = "either"
+version = "1.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
+
+[[package]]
name = "encode_unicode"
version = "0.3.6"
source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -684,6 +690,7 @@
"futures",
"hostname",
"indicatif",
+ "itertools",
"nixlike",
"once_cell",
"peg",
@@ -1127,6 +1134,15 @@
]
[[package]]
+name = "itertools"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1c173a5686ce8bfa551b3563d0c2170bf24ca44da99c7ca4bfdab5418c3fe57"
+dependencies = [
+ "either",
+]
+
+[[package]]
name = "itoa"
version = "1.0.9"
source = "registry+https://github.com/rust-lang/crates.io-index"
Cargo.tomldiffbeforeafterboth--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,2 +1,3 @@
[workspace]
members = ["crates/*", "cmds/*"]
+resolver = "2"
cmds/fleet/Cargo.tomldiffbeforeafterboth--- a/cmds/fleet/Cargo.toml
+++ b/cmds/fleet/Cargo.toml
@@ -34,3 +34,4 @@
futures = "0.3.17"
tracing-indicatif = "0.3.5"
indicatif = "0.17.7"
+itertools = "0.11.0"
cmds/fleet/src/cmds/build_systems.rsdiffbeforeafterboth--- a/cmds/fleet/src/cmds/build_systems.rs
+++ b/cmds/fleet/src/cmds/build_systems.rs
@@ -2,8 +2,9 @@
use crate::command::MyCommand;
use crate::host::Config;
-use anyhow::Result;
+use anyhow::{anyhow, Result};
use clap::Parser;
+use itertools::Itertools;
use tokio::{task::LocalSet, time::sleep};
use tracing::{error, field, info, info_span, warn, Instrument};
@@ -12,6 +13,9 @@
/// Do not continue on error
#[clap(long)]
fail_fast: bool,
+ /// Disable automatic rollback
+ #[clap(long)]
+ disable_rollback: bool,
/// Run builds as sudo
#[clap(long)]
privileged_build: bool,
@@ -39,6 +43,9 @@
pub(crate) fn should_activate(&self) -> bool {
matches!(self, Self::Switch | Self::Test)
}
+ pub(crate) fn should_schedule_rollback_run(&self) -> bool {
+ matches!(self, Self::Switch | Self::Test)
+ }
}
enum PackageAction {
@@ -103,6 +110,62 @@
InstallationCd,
}
+struct Generation {
+ id: u32,
+ current: bool,
+ datetime: String,
+}
+async fn get_current_generation(config: &Config, host: &str) -> Result<Generation> {
+ let mut cmd = MyCommand::new("nix-env");
+ cmd.comparg("--profile", "/nix/var/nix/profiles/system")
+ .arg("--list-generations");
+ // Sudo is required due to --list-generations acquiring lock on the profile.
+ let data = config.run_string_on(&host, cmd, true).await?;
+ let generations = data
+ .split('\n')
+ .map(|e| e.trim())
+ .filter(|&l| l != "")
+ .filter_map(|g| {
+ let gen: Option<Generation> = try {
+ let mut parts = g.split_whitespace();
+ let id = parts.next()?;
+ let id: u32 = id.parse().ok()?;
+ let date = parts.next()?;
+ let time = parts.next()?;
+ let current = if let Some(current) = parts.next() {
+ if current == "(current)" {
+ Some(true)
+ } else {
+ None
+ }
+ } else {
+ Some(false)
+ };
+ let current = current?;
+ if parts.next().is_some() {
+ warn!("unexpected text after generation: {g}");
+ }
+ Generation {
+ id,
+ current,
+ datetime: format!("{date} {time}"),
+ }
+ };
+ if gen.is_none() {
+ warn!("bad generation: {g}")
+ }
+ gen
+ })
+ .collect::<Vec<_>>();
+ let current = generations
+ .into_iter()
+ .filter(|g| g.current)
+ .at_most_one()
+ .map_err(|_e| anyhow!("bad list-generations output"))?
+ .ok_or_else(|| anyhow!("failed to find generation"))?;
+ Ok(current)
+}
+
impl BuildSystems {
async fn build_task(self, config: Config, host: String) -> Result<()> {
info!("building");
@@ -155,6 +218,7 @@
loop {
let mut nix = MyCommand::new("nix");
nix.arg("copy")
+ .arg("--substitute-on-destination")
.comparg("--to", format!("ssh://root@{host}"))
.arg(&built);
match nix.run_nix().await {
@@ -169,21 +233,107 @@
}
}
if let Some(action) = action {
- if action.should_switch_profile() {
+ let mut failed = false;
+ // TODO: Lockfile, to prevent concurrent system switch?
+ // TODO: If rollback target exists - bail, it should be removed. Lockfile will not work in case if rollback
+ // is scheduler on next boot (default behavior). On current boot - rollback activator will fail due to
+ // unit name conflict in systemd-run
+ if !self.disable_rollback {
+ let _span = info_span!("preparing").entered();
+ info!("preparing for rollback");
+ let generation = get_current_generation(&config, &host).await?;
+ info!(
+ "rollback target would be {} {}",
+ generation.id, generation.datetime
+ );
+ {
+ let mut cmd = MyCommand::new("sh");
+ cmd.arg("-c").arg(format!("mark=$(mktemp -p /etc -t fleet_rollback_marker.XXXXX) && echo -n {} > $mark && mv --no-clobber $mark /etc/fleet_rollback_marker", generation.id));
+ if let Err(e) = config.run_on(&host, cmd, true).await {
+ error!("failed to set rollback marker: {e}");
+ failed = true;
+ }
+ }
+ // Activation script also starts rollback-watchdog.timer, however, it is possible that it won't be started.
+ // Kicking it on manually will work best.
+ //
+ // There wouldn't be conflict, because here we trigger start of the primary service, and systemd will
+ // only allow one instance of it.
+ if action.should_schedule_rollback_run() {
+ let mut cmd = MyCommand::new("systemd-run");
+ cmd.comparg("--on-active", "3min")
+ .comparg("--unit", "rollback-watchdog-run")
+ .arg("systemctl")
+ .arg("start")
+ .arg("rollback-watchdog.service");
+ if let Err(e) = config.run_on(&host, cmd, true).await {
+ error!("failed to schedule rollback run: {e}");
+ failed = true;
+ }
+ }
+ }
+ if action.should_switch_profile() && !failed {
info!("switching generation");
let mut cmd = MyCommand::new("nix-env");
cmd.comparg("--profile", "/nix/var/nix/profiles/system")
.comparg("--set", &built);
- config.run_on(&host, cmd, true).await?;
+ if let Err(e) = config.run_on(&host, cmd, true).await {
+ error!("failed to switch generation: {e}");
+ failed = true;
+ }
}
- if action.should_activate() {
+ if action.should_activate() && !failed {
+ let _span = info_span!("activating").entered();
info!("executing activation script");
let mut switch_script = built.clone();
switch_script.push("bin");
switch_script.push("switch-to-configuration");
let mut cmd = MyCommand::new(switch_script);
cmd.arg(action.name());
- config.run_on(&host, cmd, true).await?;
+ if let Err(e) = config.run_on(&host, cmd, true).in_current_span().await {
+ error!("failed to activate: {e}");
+ failed = true;
+ }
+ }
+ if !self.disable_rollback {
+ {
+ let _span = info_span!("rollback").entered();
+ if failed {
+ info!("executing rollback");
+ let mut cmd = MyCommand::new("systemctl");
+ cmd.arg("start").arg("rollback-watchdog.service");
+ if let Err(e) = config.run_on(&host, cmd, true).await {
+ error!("failed to rollback: {e}");
+ }
+ } else {
+ info!("marking upgrade as successful");
+ let mut cmd = MyCommand::new("rm");
+ cmd.arg("-f").arg("/etc/fleet_rollback_marker");
+ if let Err(e) =
+ config.run_on(&host, cmd, true).in_current_span().await
+ {
+ error!("failed to remove rollback marker. This is bad, as the system will be rolled back by watchdog: {e}")
+ }
+ }
+ }
+ {
+ let _span = info_span!("disarm").entered();
+ info!("disarming watchdog, just in case");
+ {
+ let mut cmd = MyCommand::new("systemctl");
+ cmd.arg("stop").arg("rollback-watchdog.timer");
+ if let Err(_e) = config.run_on(&host, cmd, true).await {
+ // It is ok, if there was no reboot.
+ }
+ }
+ if action.should_schedule_rollback_run() {
+ let mut cmd = MyCommand::new("systemctl");
+ cmd.arg("stop").arg("rollback-watchdog-run.timer");
+ if let Err(e) = config.run_on(&host, cmd, true).await {
+ error!("failed to disarm rollback run: {e}");
+ }
+ }
+ }
}
}
}
cmds/fleet/src/command.rsdiffbeforeafterboth--- a/cmds/fleet/src/command.rs
+++ b/cmds/fleet/src/command.rs
@@ -143,12 +143,14 @@
pub async fn run_nix_string(self) -> Result<String> {
let str = self.clone().into_string();
- let cmd = self.into_command();
+ let mut cmd = self.into_command();
+ cmd.arg("--log-format").arg("internal-json");
run_nix_inner_stdout(str, cmd, &mut NixHandler::default()).await
}
pub async fn run_nix(self) -> Result<()> {
let str = self.clone().into_string();
let mut cmd = self.into_command();
+ cmd.arg("--log-format").arg("internal-json");
cmd.stdout(Stdio::inherit());
run_nix_inner(str, cmd, &mut NixHandler::default()).await
}
@@ -410,7 +412,6 @@
handler: &mut dyn Handler,
) -> Result<Option<String>> {
info!("running {str}");
- cmd.arg("--log-format").arg("internal-json");
cmd.stderr(Stdio::piped());
cmd.stdout(Stdio::piped());
let mut child = cmd.spawn()?;
cmds/fleet/src/main.rsdiffbeforeafterboth--- a/cmds/fleet/src/main.rs
+++ b/cmds/fleet/src/main.rs
@@ -1,3 +1,5 @@
+#![feature(try_blocks)]
+
pub mod cmds;
pub mod command;
pub mod host;
@@ -6,16 +8,14 @@
mod fleetdata;
use std::ffi::OsString;
-use std::io;
use std::time::Duration;
-use anyhow::{anyhow, bail, Result};
+use anyhow::{bail, Result};
use clap::Parser;
use cmds::{build_systems::BuildSystems, info::Info, secrets::Secrets};
use host::{Config, FleetOpts};
use indicatif::{ProgressState, ProgressStyle};
-use tokio::fs;
use tokio::process::Command;
use tracing::{info, metadata::LevelFilter};
use tracing_indicatif::IndicatifLayer;
@@ -79,9 +79,6 @@
Opts::Prefetch(p) => p.run(config).await?,
};
Ok(())
-}
-fn elapsed_subsec(state: &ProgressState, writer: &mut dyn std::fmt::Write) {
- let _ = writer.write_str(&format!("{:?}", state.elapsed()));
}
#[tokio::main]
cmds/install-secrets/Cargo.tomldiffbeforeafterboth9env_logger = "0.10.0"9env_logger = "0.10.0"10log = "0.4.14"10log = "0.4.14"11nix = "0.26.1"11nix = "0.26.1"12serde = "1.0.130"12serde = { version = "1.0.130", features = ["derive"] }13serde_json = "1.0.89"13serde_json = "1.0.89"14clap = { version = "4.0.29", features = [14clap = { version = "4.0.29", features = [15 "derive",15 "derive",nixos/modules/module-list.nixdiffbeforeafterboth--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -2,4 +2,5 @@
../fleetPkgs.nix
../meta.nix
../secrets.nix
+ ../rollback.nix
]
nixos/rollback.nixdiffbeforeafterboth--- /dev/null
+++ b/nixos/rollback.nix
@@ -0,0 +1,45 @@
+{config, ...}: {
+ # TODO: Make it work with systemd-initrd approach.
+ # In this case we can't just switch generation and re-run activation script, since the root filesystem might not be
+ # mounted yet. We need to explicitly remove the last generation, and this needs deeper integration with systemd/grub/
+ # whatever user uses. boot.json also might help here.
+
+ systemd.services.rollback-watchdog = {
+ description = "Rollback watchdog";
+ script = ''
+ set -eu
+ if [ -f /etc/fleet_rollback_marker ]; then
+ echo "found the rollback marker, switching to older generation"
+ target=$(cat /etc/fleet_rollback_marker)
+ echo "rolling back profile"
+ nix profile rollback --profile /nix/var/nix/profiles/system --to "$target"
+ echo "executing activation script"
+ "/nix/var/nix/profiles/system-$target-link/bin/switch-to-configuration" switch
+ echo "removing rollback marker"
+ rm -f /etc/fleet_rollback_marker
+ else
+ echo "rollback marker was removed, upgrade is succeeded"
+ fi
+ '';
+ path = [
+ # Should have nix-command support
+ config.nix.package
+ ];
+ serviceConfig.Type = "exec";
+ unitConfig = {
+ X-StopOnRemoval = false;
+ };
+ };
+
+ systemd.timers.rollback-watchdog = {
+ description = "Timer for rollback watchdog";
+ wantedBy = ["timers.target"];
+ timerConfig = {
+ OnUnitActiveSec = "3min";
+ RemainAfterElapse = false;
+ };
+ unitConfig = {
+ ConditionPathExists = "/etc/fleet_rollback_marker";
+ };
+ };
+}
pkgs/fleet-install-secrets.nixdiffbeforeafterboth--- a/pkgs/fleet-install-secrets.nix
+++ b/pkgs/fleet-install-secrets.nix
@@ -6,7 +6,7 @@
name = "${pname}-${version}";
src = ../.;
- cargoBuildFlags = "-p ${pname}";
+ buildAndTestSubdir = "cmds/install-secrets";
cargoLock = {
lockFile = ../Cargo.lock;
outputHashes = {